Option 1 -> Indicates movement parallel to or following the course of the canal, which suits cruising for a distance.
Option 2 -> Suggests movement from one side to the other, inappropriate for a journey of "a few miles."
Option 3 -> Implies passing from one end to the other or inside something, less natural for describing a cruise on a canal.
Option 4 -> Means approaching or reaching a point, grammatically incorrect in this context.
Hence, Option 1: along -> "Along" is the most appropriate preposition when describing movement that follows the length or course of something like a canal. Cruising "along the canal" naturally conveys traveling beside or following the waterway for an extended distance -> correct